Kktvelop



UNITED srATEs PATENT OFFICE.,

WILLIAM B. CVOATES, OF PHILADELPHIA, PENNSYLVANIA.

ENvELor.

Specication of Letters Patent No. 15,475, datedAugust 5, 1856.

To all whom 'it may concern.

Be it known that I, WILLIAM B. CoATEs,

i of the city of Philadelphia and State of Pennsylvania, have invented a new and useful Improvement in Envelops; and I do hereby declare that the following is a full, clear, and eXact description of the same, reference being had to the accompanying drawing and to the letters of reference marked thereon.

My invention consists in manufacturing envelops with a second or eXtra turn-down or fold, having adhesive material above and below, in addition to the ordinary turndown with its adhesive material; the said additional or eXtra turn-down being so arranged on the envelop as to be folded down within the same and be fastened with its adhesive material to the folds of a letter or other inclosed document, thereby preventing the latter from being removed by any of the means usually employed for effecting that object without attempts to do so being readily detected.

In order to enable others skilled in the art to make and use my invention I will now proceed to describe its construction and operation.

The perspective view in the accompanying drawing, which forms a part of this specification represents my improvements in envelops.

'Ihe body of the envelop is constructed in the usual manner with the permanent folds or turn-down a, b and b and the loose fold or turn-down al. Inside the latter I secure with any suitable adhesive substance an additional fold or turn-down e the joint of which coincides with that of the first. In the permanent turn-down a is a slit f through which is passed a string having on each end a wafer i and z, one of the wafers (z') remaining outside and other inside the turn-down. In the loose turn-down d is likewise a slit coinciding (when the envelop is closed) with the slit in the permanent turn-down a. To the inside of the second turn-down e I attach a wafer or other suitable adhesive substance 7L and the same with the outside of the turn down, which is folded and introduced into the envelop above the inclosed letter or other document in such a manner that the wafer or other adhesive material it may be caused to adhere to some blank or unwritten portion of the letter.

Care should be taken in folding the letter before placing it inside the envelop that the ends are turned down and the edges folded into each other so that the adhesive matter /L will secure the folds of the letter together. This adhesive matter is then wetted as well as the wafer z' inside the envelop, and the second fold e of the latter is introduced so that its underside bears with its adhesive substance h on the folds of the letter, the wetted wafer h remaining between the upper side of the turn-down e and the under side of the permanent fold a. The whole are then pressed together by a suitable stamp after which t-he outside wafer z' with its string is passed through the slit in the first turn-down l the adhesive material under which is wetted and pressed down on the permanent fold of the envelop. The wafer z' is subsequently wetted and attached to the upper surface of the first turn-down Z above, or partially above its slit, so that a portion of the wafer will adhere to the permanent fold a. The wafers may be attached to the string either by passing the ends of the latter through an orifice in each wafer and subsequently tying the same, or by making use of double wafers at each end of the string, the latter being pressed between the two wafers when they are in a damp state.

Supposing an attempt was made to abstract a letter from an envelop, secured as above by cutting the edges, it is evident that with the letter folded as described, and its folds stuck together by the adhesive material on the underside of the second fold e, neither the letter or its contents could be removed without mutilating the seal or destroying the envelop.

Should an attempt be made on the other hand to remove the contents of the letter by steaming or damping the adhesive substances which form the exterior seal, it would be discovered that the efforts would be unsuccessful on account of the adhesive substance which forms Jthe interior seal. In both cases any attempt to abstract the contents of the envelop, or in any way tamper with the same, would be at once detected by its appearance.

The object of my improved envelop, however, is not so much that of detecting the mutilation of or attempts to abstract letters from the same by dishonest oficials or (what I believe to be a more frequent occurrals, independent of the connected wafers, afford an efficient security, but

Vhat I claim and desire to secure by Letters Patent is The construction of envelops with an eXtra turn-down e said turn-down being furnished with adhesive substance7 and being arranged substantially in the manner and for the purpose herein set forth.

WILLIAM B. COATES. Witnesses:

HENRY HoWsoN, DAVID MATTHEW. 

